PROJECT SUMMARY/ABSTRACT This patient-oriented research R21 application will provide funding support for validating a novel approach for screening older adults for mild cognitive impairment (MCI of the Alzheimer?s type) and Alzheimer?s disease (AD), an area of substantial and increasing significance. Unlike common questionnaires that are subjective and often stressful, our proposed innovative screening method is objective, quick, and based on combined biomechanical motor and cognitive performance ?dual-tasking? assessment, inclusive of low-cost wearable sensor technology. By assessing sensor based differences between an individual?s upper-extremity single-task motor performance, and dual-task motor plus cognitive task performance, we will determine dual-task ?cost?. We will determine dual- task cost for both traditional measures of motor performance, in addition to nonlinear dynamics of the motion. We have previously developed an upper-extremity function (UEF) test, to obviate the need for walking tasks in high risk elders. The UEF test involves repetitive elbow flexion measured using low-cost sensors, which is easily performed (standing, sitting, or in bed) in less than one minute. Post-processing, and scoring is performed in less than one minutes. We have patented and validated the functional component of this test based on frailty scales for older adults. The proposed approach builds upon pilot research performed by an excellent group of interdisciplinary investigators at the Banner Sun Health Research Institute in collaboration with the University of Arizona Center on Aging and the Arizona Alzheimer?s Consortium, demonstrating significant associations between UEF dual- task performance/cost (i.e., elbow flexion accompanied by counting backwards) with both the Mini Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scores, both common gold standard cognition screening questionnaires for older adults (? 65 years). The goal of the proposed R21 is to further develop, refine, and validate a UEF cognitive index in older adults with clinically confirmed MCI and AD. Of note, we will use three groups of neuropsychologically and diagnostically confirmed participants: 1) those who are free of cognitive impairment, 2) those with MCI, and 3) those with early stage AD. We will explore the association of specific cognition domains (e.g., memory, attention, executive functioning, etc.) that are known to be associated with dual-tasking performance. We expect to extend scientific knowledge regarding the nature of dual-tasking based on neuropsychological evidence, focusing on a novel upper-extremity function measure (rather than gait assessment). From a clinical viewpoint, we expect to validate a quick and accurate objective tool for screening of MCI and AD, with the ultimate goal of supporting the triple aim and the increasingly incidence of AD by providing a quick and cost-effective screening tool to support the quality of life and independence of older adults.